Tripod-top for photographic cameras



(No Model.)

T. H. BLAIR.

TRIPOD TOP FOR PHOTOGRAPHIO CAMERAS.

No. 364,629. Patented June 14,1887.

UNITED. STATES PATENT OF ICE.

THOMAS H. BLAIR, or 'nosron, MASSACHUSETTS.

TRIPOD-TOP FOR PHOTOGRAPHIC CAMERAS.

SPECIFICATION forming part of Letters Patent No. 364,629, dated .l'unc14, 1887.

Application filed January 22,1887. Serial No. 225,146. (No model.) v

To all whom it may concern:

Be it known that I, THOMAS H. BLAIR, a citizen of the United States,residing at Boston, in the county of Suffolk and State of Massachusetts,have invented certain new and useful Improvements in Tripod-Topsfor'Photographic Cameras; and I do hereby declare the following to be afull, clear, and exact descrip- 'of the legs of thetripod-top-ontwardlyor away from the bolt 'by which the camera-box issecured.

Figure 1 of the drawings represents a perspective view; Fig. 2, ahorizontal central section. Fig. 3 is an elevation with the tripodcomplete and set up.

Hitherto, in the manufacture and construction of tripod-tops forphotographic cameras, they have been made triangular in general shape,while thelegs of the tripod have all been disposed at the same fixeddistance from the center of said tripod. The latter is at this pointprovided with a bolt orpin upon which the camera-box secured thereto ispivoted.

It is evident that when the camera box is mounted upon, its tripod, andwith the bellows. extended for focusing purposes, there is no supportbeneath and in the rear for this now projecting part of the camera-box.The latter now tends to tip back, and-in outdoor work vibrations andunsteadiness of the camera-box are increased.

My invention has for its object such a change in the construction andshape of the tripodtop that the rear portion of the camera-box, whetherthe bellows are extended or not, shall be furnished with a firm andstable support; andhenceIhave made oneof the tripod-legs ad justableupon the tripod-top; consequently, by

moving the pivotal point of attachment of such leg outwardly upon thetripod-top, the size of the latter is practicallyincreased and stabilityof the entire apparatus produced.

To this end I have shown at A a tripod-top out preferably from wood ofany desired thickness, which is formed of a rectangular portion or arm,B, provided with two very much shorter but similarly-shaped arms, 0 D.These parts are so arranged with respect to each other that theircentral longitudinal axes emabetter balanced, and consequently there isless liability to vibrate. The bolthole a, to 0011- tain the boltwhereby the camerabox is secured to theiripod, is placed in the top A,coincident with the center of a circle which would circumscribe the arms'0 D, while the legs are to be removabl y secured to the tripodtop inthe holes 1 1, 2 2, 3 3, 4 4, straddling the arms to which they areattached; hence when the apparatus is in position for work,with thebellows extended and the plate-holder in position, all the weight isalong the longitudinal axis of the arm B, which is firmly upheld by thetripod-leg securedthereto by the holes 44. A series of holes, 4 4, maybe disposed as shown, and thus the position of the leg attached to itmay be changed to suit circumstances at any point along the arm B.Furthermore, I have provided the holes 3 3,which thus enable me .toarrange all the tripod-legs at equal distances from the bolt-hole a,after the usual manner of disposing them,while the arm B, by itssuperior length, still affords additional security to the rear andextensible part of the camera-box'and renders it much more steady,sincethe strain through the bolt-' hole a is very much diminished.

The changes in the positions of the leg c0- operating with the long armB are suflicient to enable the operator to use the same tripod forvarying sizes of camera-boxes. Thus for a small size the legs may besecured as usual; but in the event of a large box with a longfocusedlens being employed, the leg, now securedsay at 3 3-is shifted outwardlyto the holes 4 4 or 4 4, as may be desired; hence it is evident thatthis tripod combines all the good points of the ordinary tripod, withthe increased advantages that for outdoor work in windy weather, or atany desired moment when increased steadiness is wanted, it can easilyand readily be obtained.

I am aware that it is not new to provide a tripod-top with three devicesfor attaching the legs, the relative positions of these devicescorresponding to those of the three arms of my tripod-top. Thisconstruction I do not claim; but

I claim 1. In a tripod, the combination, with the tripod-legs removablyattached to the tripodtop, of a tripod-top formed with two short arms, 0D, and a long arm, B, the rear tripod leg cooperating with the latter,being adjustable toward or away from the central bolt-hole,

a, substantially as and for the purposes herein stated.

2. The combination, with a tripod-top to which are removably securedtripod-legs, of a leg adjustable toward or away from the bolt whichsecures the camera-box,substantially as described.

3. A tripod-top, A, formed of the arms B C D, provided with thebolt-hole a, and laterally

